1. Field of the Invention
This invention is generally directed to methods and devices utilized in the construction of reinforced concrete block walls and more specifically to barriers or forms for closing inspection openings created in concrete blocks for the purposes of permitting visual inspection of reinforcing rods extending through the block walls. In the preferred embodiments, the forms are constructed of transparent plastic materials which are shaped so as to be seated within inspection openings formed in the concrete blocks and which are installed so as to be recessed within the openings. The forms or inspection windows include flanges or clips which are seated against the inner face of the core or cells of concrete blocks as the cells of the blocks are filled with cementitious material following the erection of a wall structure. In some embodiments the forms include two or more components which are relatively adjustable with respect to one another so that the size, i.e. height and/or width, of the forms may be selectively varied.
2. History of the Related Art
In many geographic locations it is required that walls formed of hollow core concrete blocks be reinforced with steel rods which function to anchor the walls to the concrete foundation or footings. In those areas where structures are subjected to environmental conditions such as hurricanes or tornadoes, it is necessary to ensure that the wall components of a building ar suitably anchored to the footings of the structure to prevent destruction of the walls in the case of inclement weather. The reinforcing rods are normally buried within the concrete footings and extend vertically upward for a distance of two to three feet. The reinforcing rods are generally spaced at various distances which are established by local codes. By way of example, in some areas such reinforcing rods are required at intervals of either eight or sixteen feet and at each corner of a wall structure, depending upon the height of the wall and the end use for which the structure is being built.
During the initial phases of concrete wall construction at each point at which a hollow concrete block is seated over a reinforcing rod an inspection hole or window is created in the face of the block so as to permit building inspectors to determine that proper tying of steel reinforcing rods is accomplished before the wall is completed. As each course of concrete blocks is laid the cells of the blocks are aligned vertically above each of the reinforcing dowel rods extending upwardly from the foundation. After the required number of courses of concrete blocks have been laid, reinforcing steel rods are extended vertically through the aligned cells above each of the reinforcing bars extending from the foundation with the end portions of the bars being joined utilizing metallic ties. The uppermost portion of the wall reinforcing bars are thereafter united to horizontally oriented reinforcing bars which extend along the upper lintel block course. In this manner the blocks are connected both horizontally and vertically to the floor or foundation.
After the proper tying of the vertically oriented steel rods to the foundation steel rods has been approved by an engineer or building inspector, the aligned cells of the concrete blocks through which the steel extends must be filled with a cementitious material such as a concrete or grout mixture. By pumping the cementitious material into the aligned cells of the concrete blocks, continuous reinforced concrete columns are formed which columns unite the steel and concrete blocks throughout the height of the masonry construction.
One of the problems associated with reinforced concrete block construction is that each of the inspection openings created in the lower course of concrete blocks must be sealed prior to the vertically aligned cells being filled with cementitious material. Traditionally, workers place a board or other barrier against the front face of the block wall and thereafter utilize different reinforcing techniques to apply pressure to the barrier from the outside to seal the openings. Frequently, due to the amount of pressure on the barriers utilized to seal the inspection openings, the boards or other barriers will be forced outwardly from the face of the wall as the cementitious material is being poured. In worst instances, the barriers will fail thereby allowing cementitious material to pour out the openings in the blocks and thus requiring additional time and labor to be expended to remove the material which has "blown out" through the openings. Thereafter new forms must be installed to seal the openings and additional cementitious material pumped into the vertically aligned cells. This problem is complicated in corner areas where the openings are frequently formed along two sides of a block thereby requiring that two forms be applied to the surface of the block to retain cementitious material therein during the cell filling process.
Even in those instances where the forms for sealing the inspection openings in concrete blocks do not fail completely, the forms or barriers will frequently shift allowing some cementitious material to flow outwardly with respect to the front face of the concrete wall. In these instances, it is necessary for workers to chisel off the protruding concrete material which sets up and forms a rough surface on the face of the concrete wall in order to provide a smooth finished appearance to the wall.
In an effort to reduce failure of the barriers or forms which are utilized to seal the inspection openings in concrete blocks, one company has developed a product which utilizes hook elements which are embedded between the vertical courses of concrete blocks adjacent each edge of the inspection openings. After the wall is formed, a bar is inserted into the hooks and thereafter wedges driven between the bar and the face of the concrete blocks against boards which are placed over the inspection openings. Such a technique is time consuming and laborious. Further, once an opening has been sealed, it is necessary to remove the wedge elements, boards, and cut the metallic hooks and drive the protruding end portions thereof back into the wall. Also, utilizing such a technique, it is not possible to ensure that the cementitious material which has been pumped into a vertically aligned column of concrete block cells actually fills the entire column as the inspection opening is covered with an opaque material.
In some instances, as the cores or cells of concrete blocks are being sealed with cementitious material, air pockets may be created which prohibit or prevent the cementitious material from completely filling a column of cells, thereby creating voids which effect the integrity of the reinforced wall structure. When an inspection opening is sealed so that it is impossible to view the opening until after the cementitious material has been poured and set, there is no way to ensure that the column is completely filled until after the initially placed material sets or hardens.
Some examples of prior art construction techniques and construction blocks which utilize windows of various types are disclosed in U.S. Pat. Nos. 1,809,385 to Liptak, 2,115,264 to Henderson, 3,330,079 to Mitchell et al., and 4,145,861 to Yarnick. In addition, reference is made to applicant's co-pending patent application, filed concurrently herewith, and entitled MASONRY INSPECTION BLOCK, which is directed to structures for concrete blocks having preformed or molded inspection openings provided in the blocks for purposes of facilitating the sealing of the openings therein in a manner as taught by the present application. The contents of the co-pending application are contained herein by reference.